Method of forming dense packages of textile fibers



Nov. 2, 1965 D. B. cooK 3,214,798

METHOD OF FORMING DENSE PACKAGES OF TEXTILE FIBERS Filed Jan. 14, 1965 l5" PRE$$URE I 5OUECE- III HIGH FIZEQUENCY POWER QM i INVENTOR. bE-WEY B. COOK wwmsmh United States Patent METHQD 0F FORMING DENSE PACKAGES 0F TEXTILE FIBERS Dewey B. Cook, Johnsonvilie, S.C., assignor to Wellman Comhing Company, Johnsouville, S.C., a corporation of Delaware Filed Jan. 14, 1963, Ser. No. 251,408 6 Claims. ((31. 19-66) This invention relates generally to textile fiber processing, and more particularly to a novel process for forming packages of textile fibers in sliver form, for example, which packages aid in the handling, storage and transportation of such fibers prior to the ultimate formation of yarn therefrom.

Storing and shipping of fibers in sliver form creates problems. For example, owing to the bulky nature of the sliver, the packages thereof are also bulky in com parison to the amount of fibers contained in the package. This creates space problems and increasing transportation cost. Moreover, it is axiomatic to point out that handling costs of the packages increase with the bulkiness thereof.

Others have made attempts to solve the foregoing problems, but their solutions have only created additional problems. For example, it has grown into practice to package coiled sliver in thin plastic bags. In such cases the coiled sliver is compressed to some degree, and while compressed, the bag is closed around the coil. This method does reduce the bulk of the sliver to some degree, but it is by no means a panacea for the bulk problem. Moreover, when the bags are opened or broken acci dentally, the coiled sliver rapidly expands toward its orig inal uncompressed height, thus creating obvious problems in handling.

Another example of an attempted solution is a process wherein a hot fluid, such as hot air or hot water, or, preferably steam at low pressure and a cooling fluid, such as air, are sequentially forced through a compressed and confined mass of fibers and, while the fibers are so confined, to set the fibers in the compressed condition. This process although resulting in a highly compressed, nonbulky package, has definite drawbacks arising out of the fact that the introduction of the hot fluid into the mass detrimentally alters the moisture uniformity of the mass, such as by the creation of wet spots, and alters the moisture content of the mass which, in turn, can seriously affect subsequent fiber processing operations.

This type of process is disclosed in US. Patents Nos. 2,707,806 and 2,708,838 to R. C. Wilkie.

In accordance with the present invention, I have found that all of the foregoing problems in fiber package formation can be eliminated by dielectrically heating a compressed mass of fibers with the result that an extremely hard, compressed, self-sustaining package of such fibers is formed without any appreciable effect upon the moisture existing in the package prior to the dielectric heatsetting operation.

Accordingly, it is a primary object of this invention to provide a process of forming a compressed, self-sustaining package of textile fibers, such as in sliver form, wherein the normal moisture content present in the mass of fibers prior to compression thereof is virtually unaifected during the formation of the compressed package.

It is a more specific object of this invention to provide a process for forming a compressed, self-sustaining package of textile fibers employing dielectric heating in setting the fibers in a compressed condition.

It is a further more specific object of the invention to provide a process of forming a compact self-sustaining package of textile fibers, such as wool, by compressing a mass of loose textile fibers and then subjecting the same 3,214,79 Patented Nov. 2, 1965 to a high frequency electrical field to maintain the mass of fibers in a compact state and wherein the fibers are virtually instantaneously aged or relaxed by the dielectric treatment serving to reduce the inherent springiness of the fibers to thereby avoid the conventional practice of storing the fibers for long periods of time for the relax ing or aging thereof.

Some of the objects of the invention having been stated, other objects will appear as the description proceeds when taken in connection with the accompanying drawings, in Which- FIGURE 1 is an elevational View partially in section and with parts broken away of a can containing uncompressed coiled sliver beneath an apparatus for compressing such sliver;

FIGURE 2 is a view similar to FIGURE 1 showing the apparatus in extended position and the coiled sliver compressed; and

FIGURE 3 is a horizontal sectional view of a compressed mass of coiled sliver taken along lines 3-3 of FIGURE 2.

Referring now to the drawings, I have chosen to show, as a specific and non-limiting schematic illustration of the method of my invention, the formation of a compressed, dielectrically heat-set package of coiled sliver.

More specifically, the reference numeral 10 depicts a loose, springy mass of coiled wool sliver as formed by the coiler head of a gilling machine, for example. Conventionally, such mass of coiled sliver measures about fifteen inches in diameter and has a height of about five feet. The coiled sliver 10 is contained by a cylindrical, open ended can 11 which may be a conventional sliver can. Preferably, the can is provided with electrically nonconductive side walls and is provided with an electrically conductive bottom plate 12, for reasons which will become apparent as the description of the invention proceeds.

As shown, the can 11 containing the coiled sliver 10 is placed in an upright position below a vertically mounted, suitably suspended hydraulic ram, broadly indicated at 13, which is connected to a suitable pressure source. The ram 13 comprises a cylinder 14 containing a piston 15 with an operating rod 16 connected thereto and extending outside the cylinder 14. The outer end of the operating rod 16 is provided with a circular pressure plate 17, the diameter of which corresponds substantially to the internal diameter of the can 11. For reasons which will become apparent as the description proceeds, the plate 17 is made of electrically conductive material and is electrically insulated from the operating rod 16.

As shown in FIGURE 2, a source of high frequency power indicated diagrammatically at 20 is provided adjacent the can 11 and is electrically connected through cables 21 to the bottom plate 12 and the pressure plate 17, both of which are made of electrically conductive material, as previously pointed out, and accordingly, serve as electrodes for the power source 20. The power source 20 is of the type containing a conventional high frequency oscillator, preferably capable of producing a frequency of about 2 to megacycles.

As further shown in FIGURE 2, upon actuation of the hydraulic ram 13, the pressure plate 17 is moved downwardly into the can to compress the coiled sliver 10, preferably to less than one-fifth its original height. Thereafter, upon application of current to the plates 12 and 17 by the power source 20, heat is uniformly generated within the coiled sliver 10. From tests to date, this dielectric heating is preferably continued, in the case of wool, until a temperature of about 220 F. is reached within the mass of fibers. This reqiures about two minutes. The heating is then discontinued by the elimination of the current to the plates 12 and 17 while preferably maintaining the pressure on the mass for an additional period of two minutes. Thereafter, the pressure plate 17 is retracted with the result that the coiled sliver 10 regains no more than about of its original height, thus resulting in a final height of about 20% that of the uncompressed mass.

The compressed self-sustaining mass of dielectrically heat-set fibers is then removed from the can 11 and wrapped, if desired, and is shipped and/or stored as requirements dictate.

Although the action of the dielectric treatment of the fibers may not be completely understood, it is clear that such treatment generates heat within the mass itself and causes the fibers to be set in their compressed condition by reducing the normal springiness thereof. Moreover, since this setting is accomplished without the necessity for introducing heat or coolant from an outside source and without the necessity for raising the temperature appreciably beyond the vaporization temperature of the moisture contained in the mass, the resulting package of set fibers has the same moisture therein in the same amount as was present in the mass of fibers prior to the setting operation. Further, such moisture is distributed in the mass of fibers in substantially the same uniform manner. As has been previously pointed out, this sameness of moisture content and uniformity is most desirable, if not critical, in subsequent processing of the fibers.

In the drawings and specification there has been set forth a preferred embodiment of the invention and, al though specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention being defined in the claims.

I claim:

1. A method of forming a self sustaining compact package of textile fibers from a loose springy mass of fibers in uncompressed form without appreciably disturbing a predetermined level and distribution of moisture present therein needed for subsequent fiber processing operations and wherein such package will retain its compact form in the absence of pressure being applied thereto, said method comprising the steps of compressing the loose mass of fibers by applying pressure thereto to compact the same and reduce the volume to the desired size package, dielectrically heating said compressed mass to reduce the normal springiness thereof while substantially maintaining said amount of moisture in said mass of fibers in its distributed condition, and thereafter releasing said pressure.

2. A method according to claim 1 wherein said fibers are in the form of a sliver, i i

3. A method according to claim 1 wherein said fibers are wool.

4. A method according to claim 3 wherein said fibers are in the form of coiled sliver.

5. A method of forming a dense package of textile fibers in coiled sliver form wherein said package will retain substantially its form and size in the absence of pressure being applied thereto, said method comprising the steps of applying pressure to a loose, springy mass of coiled sliver having a predetermined amount of substantially uniformly distributed moisture therein to compact the same and reduce the volume thereof to about 20% of the volume of the loose coiled sliver, subjecting the compacted coiled sliver to the action of a high frequency electrical field to reduce the springiness thereof and to set the coiled sliver in its compacted state while substantially maintaining said amount of moisture in said mass of fibers needed for subsequent fiber processing operations in its substantially uniformly distributed condition, and thereafter releasing said pressure.

6. A method of forming a dense package of textile fibers in coiled sliver form wherein said package will retain substantially its form and size without the application of pressure thereto, said method comprising the steps of confining in an electrically insulated container, a loose, springy mass of coiled sliver having a predetermined amount of substantially uniformly distributed moisture therein, compressing said mass by applying pressure thereto to reduce its volume to about 20% of the volume of the loose coiled sliver, subjecting the compressed coiled sliver to the action of a high frequency electrical field to reduce the springiness thereof and to set the coiled sliver in its compressed state while substantially maintaining said amount of moisture in said mass of fibers needed for subsequent fiber processing operations in its sub stantially uniformly distributed condition, discontinuing the action of said high frequency electrical field, releasing said pressure, and removing the compressed coiled sliver from the container.

References Cited by the Examiner UNITED STATES PATENTS 2,325,652 8/43 BierWiIth.

2,421,335 5/47 Kline et al. 2872 2,635,352 4/53 Phillips 21910.41 X 2,707,806 5/55 Wilkie 19-66 2,779,977 2/57 Wilkie 19-159 X A. SCl-IEEL, Primary Examiner, 

1. A METHOD OF FORMING A SELF SUSTAINING COMPACT PACKAGE OF TEXTILE FIBERS FROM A LOOSE SPRINGLY MASS OF FIBERS IN UNCOMPRESSED FORM WITHOUT APPRECIABLY DISTURBING A PREDETERMINED LEVEL AND DISTRIBUTION OF MOISTURE PRESENT THEREIN NEEDED FOR SUBSEQUENT FIBER PROCESSING OPERATIONS AND WHEREIN SUCH PACKAGE WILL RETAIN ITS COMPACT FROM IN THE ABSENCE OF PRESSURE BEING APPLIED THERETO, SAID METHOD COMPRISING THE STEPS OF COMPRESSING THE LOOSE MASS OF FIBERS BY APPLYING PRESSURE THERETO TO COMPACT THE SAME AND REDUCE THE VOLUME TO THE DESIRED SIZE PACKAGE, DIELECTRICALLY HEATING SAID COMPRESSED MASS TO REDUCE THE NORMAL SPRINGINESS THEREOF WHILE SUBSTANTIALLY MAINTAINING SAID AMOUNT OF MOISTURE IN SAID MASS OF FIBERS IN ITS DISTRIBUTED CONDITION, AND THEREAFTER RELEASING SAID PRESSURE. 